[URL="http://api.tweetmeme.com/share?url=http://espn.go.com/nfl/trainingcamp11/story/_/id/6907722/buffalo-bills-hold-kyle-williams-brad-smith-practice&service=bit.ly&source=espn"][IMG]http://api.tweetmeme.com/imagebutton.gif?url=http://espn.go.com/nfl/trainingcamp11/story/_/id/6907722/buffalo-bills-hold-kyle-williams-brad-smith-practice[/IMG][/URL]Buffalo Bills defensive lineman Kyle Williams and wildcat quarterback Brad Smith have been held out of practice for precautionary reasons due to injuries.